Transport Properties of CaSi2 and Ca2Si Thin Films

2020 ◽  
Vol 312 ◽  
pp. 3-8
Author(s):  
L. Dermenji ◽  
K.G. Lisunov ◽  
Konstantin Nickolaevich Galkin ◽  
Dmitrii L. Goroshko ◽  
E.A. Chusovitin ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetic Fields ◽  
Transport Properties ◽  
Hall Coefficient ◽  
Charge Carriers ◽  
The Other ◽  
Temperature Range ◽  
Other Hand ◽  
Complex Dependence

Resistivity, r (T), and Hall coefficient in weak (B < 1 T) magnetic fields, R (T), are investigated in Ca2Si and CaSi2 films at temperatures T between ~ 20 - 300 K. In CaSi2, r (T) is typical of metals increasing with T within the whole temperature range. On the other hand, the resistivity of Ca2Si is pertinent of semiconductors. Namely, it is activated below T ~ 200 K, exhibiting different slopes of ln r vs. T -1 plots at lower and higher T, and a weak increase between T ~ 200 - 300 K. Both materials demonstrate a complex dependence of R (T), including a change of the sign. Transport properties above have been analyzed assuming two groups of charge carriers, electrons and holes, contributing them.

Study of Hf Diffusion in A-Zr using Rutherfdrd Bacckscrttering Spectroscopy

1989 ◽  
Vol 157 ◽  
Author(s):  
F. Dyment ◽  
M. Behar ◽  
H. Oners ◽  
P.L. Grande ◽  
E. Savino ◽  
...  
Keyword(s):  
Thin Films ◽  
Diffusion Coefficients ◽  
The Other ◽  
Present Contribution ◽  
Temperature Range ◽  
Other Hand

ABSTRACTThe present contribution reports on measurements of the diffusion coefficients of Hf in a-Zr via the RBS technique. 250 8 Hf thin films were deposited on two kinds of polycrystalIine Zr samples and annealed in a 773-1115 K temperature range. Our results show that in both cases, the diffusion coefficients follow curved flrrhenius plots. On the other hand for the purest Zr sample we have obtained diffusion coefficients that are systematicaly and significativel ly lower than those corresponding to the Zr sample richer in impurities.

PTCDA Films Deposited by Ionized Beam Method

1993 ◽  
Vol 316 ◽  
Author(s):  
Hiroaki Usui ◽  
Kiyoshi Kashihara ◽  
Kuniaki Tanaka ◽  
Seizo Miyata
Keyword(s):  
Thin Films ◽  
Molecular Orientation ◽  
Chemical Structure ◽  
Chemical Change ◽  
The Other ◽  
Ion Acceleration ◽  
Ionization Condition ◽  
Other Hand ◽  
Beam Method

ABSTRACTThin films of 3,4,9,10-perylenetetracarboxylic-dianhydride (PTCDA) were deposited by an ionized beam method. The molecular orientation and chemical structure of the films were studied in connection with ionization and ion acceleration conditions. At a low ionization condition, the molecules are oriented in parallel with the substrate, and the crystallinity was improved by an appropriate ion acceleration. At higher ionization conditions, on the other hand, ion acceleration resulted in a loss of crystallinity. Deposited molecules undergo chemical change in such a condition, leading to dissociation of dianhydride groups.

Growth of Epitaxial Site-Engineered Bi4Ti3O12-Basded Thin Films by Mocvdand Their Characterization

2002 ◽  
Vol 748 ◽  
Author(s):  
Hiroshi Funakubo ◽  
Tomohiro Sakai ◽  
Takayuki Watanabe ◽  
Minoru Osada ◽  
Masato Kakihana ◽  
...  
Keyword(s):  
Thin Films ◽  
Leakage Current ◽  
Leakage Current Density ◽  
Current Density ◽  
Spontaneous Polarization ◽  
Chemical Vapor ◽  
The Other ◽  
Other Hand ◽  
La Substitution ◽  
Lower Temperature

ABSTRACTThin films of BIT, La-substituted BIT (BLT) and La- and V-cosubstituted BIT(BLTV) were epitaxially grown on SrRuO3//SrTiO3 substrates at 850°C by metalorganic chemical vapor deposition (MOCVD), and their electrical properties were systematically compared. All films on (100), (110) and (111)-oriented substrates were epitaxially grown with (001)-, (104)-/(014)-and (118) –preferred orientations, respectively. The leakage current density of the BLTV film was almost the same with that of the BLT film, but was smaller than that of BIT film, suggesting that the La substitution contributed to the decrease of the leakage current density especially in pseudoperovskite layer. Spontaneous polarization of the BLTV film was estimated to be almost the same with the BLT film but was smaller that that of the BIT film. This is explained by the decrease of Tc with the La substitution, while V did not contribute to the change of the Curie temperature (Tc ). On the other hand, the coercive field (Ec) value of the BLTV was smaller than that of the BIT and the BLT films. As a result, La substitution contributed to the decrease of the leakage current density together with the decrease of the spontaneous polarization due to the decrease of the Tc. On the other hand, V substitution contributes to the decrease of the defects that suppress the domain motion and increases the Ec value. Therefore, each substitution of La and V plays different roles and this contribution is remarkable for the films deposited at lower temperature.

Platform for in-planeZTmeasurement and Hall coefficient determination of thin films in a temperature range from 120 K up to 450 K

2016 ◽  
Vol 31 (20) ◽  
pp. 3196-3204 ◽  
Author(s):  
Vincent Linseis ◽  
Friedemann Völklein ◽  
Heiko Reith ◽  
Peter Woias ◽  
Kornelius Nielsch
Keyword(s):  
Thin Films ◽  
Hall Coefficient ◽  
Temperature Range ◽  
Image Position

Abstract

Reduction of binary sulfate mixtures containing CuSO4 by H2

1976 ◽  
Vol 54 (23) ◽  
pp. 3651-3657 ◽  
Author(s):  
Fathi Habashi ◽  
Shaheer A. Mikhail
Keyword(s):  
Intermediate Product ◽  
The Other ◽  
Temperature Range ◽  
Other Hand ◽  
First Case ◽  
Limited Temperature ◽  
Limited Temperature Range ◽  
The Individual

The reduction of a binary sulfate mixture cannot be predicted from the behavior of the individual components. Thus, while CuSO4 is reduced to Cu at 400 °C and NiSO4 is reduced to Ni3S2, the sulfate mixture yields Cu, Ni3S2, and Cu2S. Also while FeSO4 is completely stable in H2 at 400 °C, (Cu,Fe) SO4 yields Cu and Cu5FeS4. The formation of Cu2S in the first case and Cu5FeS4 in the second was unexpected. On the other hand, (Cu,Mn)SO4 is stable in H2 up to 550 °C although pure CuSO4 is completely reduced at 400 °C. CoSO4 also interferes when reduced in presence of CuSO4, while Na2SO4, MgSO4, Al2(SO4)3, ZnSO4, CdSO4 do not interfere within limited temperature range. Of these only Na2SO4 forms a complex sulfate with CuSO4. No Cu2SO4 was identified when CuSO4 was reduced in presence of other sulfates although it is an intermediate product during the reduction of pure CuSO4.

The Intercorrelation Between Microstructure and Chemicalmechanical Polish of Metal Thin Films

1999 ◽  
Vol 564 ◽  
Author(s):  
Wei-Tsu Tseng ◽  
Ying-Lang Wang
Keyword(s):  
Thin Films ◽  
Grain Size ◽  
Removal Rate ◽  
Metal Films ◽  
The Other ◽  
Metal Thin Films ◽  
Other Hand ◽  
Underlying Mechanisms ◽  
Table Speed

AbstractThe correlation between microstructures of Al and W metal thin films and their respective CMP performance is investigated. It is found that CMP removal rate decreases with increasing grain size. In both cases, the textures of the metal films are altered and their resistivity increased after CMP. The phenomenon is more pronounced for polish under a greater down force. The table speed, on the other hand, has only minimum effects on microstructure and resistivity. The possible underlying mechanisms leading to this phenomenon are proposed and their potential impacts on metallization reliability is discussed.

FERROMAGNETIC TDAE-C60 VERSUS PARAMAGNETIC TDAE-C70: FARADEY BALANCE AND ESR STUDY

1992 ◽  
Vol 06 (23n24) ◽  
pp. 3953-3958 ◽  
Author(s):  
Kazuyoshi Tanaka ◽  
Anvar A. Zakhidov ◽  
Kazunari Yoshizawa ◽  
Kenji Okahara ◽  
Tokio Yamabe ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Fullerene Molecule ◽  
The Other ◽  
Temperature Range ◽  
Type Transition ◽  
Other Hand ◽  
Spin Resonance ◽  
Ordered State

Magnetic properties of C 60 and C 70 complexes with tetrakis(dimethylamino)ethylene (TDAE) have been studied based on the measurements of the Faraday-balance magnetization and the electron spin resonance (ESR). It has been found that both TDAE- C 60 and TDAE- C 70 possess about one radical spin per fullerene molecule. TDAE- C 60 has been confirmed to show ferromagnetic-type transition at Tc=16.7–17.5 K . Appearance of a new broad and intense ESR signal below Tc of TDAE- C 60 suggests that the radical spins in the magnetically ordered state rather localize on each C 60 molecule and are ferromagnetically correlated. On the other hand, TDAE- C 70 does not show ferromagnetism in all the temperature range down to 4.5K.

Carboxy Nitroso Rubber, Chemistry, Properties, and Applications

1971 ◽  
Vol 44 (1) ◽  
pp. 40-51 ◽  
Author(s):  
N. B. Levine
Keyword(s):  
The Other ◽  
Temperature Range ◽  
Other Hand

Abstract The nitroso copolymer shows excellent promise which has not been realized due to a lack of ability to achieve a suitable cure. The CNR terpolymer, on the other hand, retains the excellent solvent and oxidizer resistance, nonflammability, and wide useful temperature range of the copolymer and can, in addition, be easily fabricated and cured by several techniques into many useful products.

scholarly journals Effect of temperature on growth of Pseudomonas protegens Pf-5 and Pseudomonas aeruginosa PRD-10 in LB Lennox medium

2018 ◽  
Author(s):  
Wenfa Ng
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Optical Density ◽  
The Other ◽  
Temperature Adaptation ◽  
Effect Of Temperature ◽  
Metabolic Processes ◽  
Two Phase ◽  
Ph Variation ◽  
Temperature Range ◽  
Other Hand

Temperature affects growth of bacteria by influencing enzyme and growth kinetics. Specifically, evolution selects for specific temperature range in which a microbe could thrive, and thus fix the temperature range in which biomolecule structure and function are finely tuned for coping with the thermal conditions prevailing within a cell at a particular temperature. Using aerobic culture in LB Lennox medium in shake flasks, this study aimed to understand the growth of Pseudomonas protegens Pf-5 (ATCC BAA-477) and Pseudomonas aeruginosa PRD-10 (ATCC 15442) at 25, 30 and 37 oC. Experiment results revealed that P. protegens Pf-5 grew very poorly at 37 oC (with maximal optical density of 0.66), while better growth was observed at 25 and 30 oC. Specifically, P. protegens Pf-5 appeared to be better adapted to growth at 25 oC, where the maximal optical density obtained was 5.3 compared to 4.6 at 30 oC. More importantly, two phase growth behaviour was observed during growth at 30 oC where a faster initial phase of growth was followed by a slower one. Growth at 25 and 30 oC exhibited similar pH trend, which suggested similar metabolic processes was activated during growth. On the other hand, P. aeruginosa PRD-10 demonstrated a more efficient conversion of LB Lennox medium into biomass where the maximal optical density obtained at all three growth temperatures were higher than those of P. protegens Pf-5. More importantly, growth of P. aeruginosa PRD-10 exhibited a clear adaptation to growth at 25 and 37 oC, while growth at 30 oC resulted in a lower biomass yield compared to that of 25 and 37 oC. On the other hand, pH variation during culture revealed that P. aeruginosa PRD-10 likely activated similar metabolic processes at all three growth temperatures, where a higher growth temperature would result in the net secretion of more alkaline metabolites. Collectively, P. protegens Pf-5 and P. aeruginosa PRD-10 demonstrated clear temperature adaptation at an evolutionary level. In addition, experiment data suggested that P. aeruginosa PRD-10 might have co-evolved with humans on a substantial time scale resulting in a temperature preference of 37 oC over 30 oC.

Differential Enthalpies of Solution of Components in Binary Systems 2 CaO . Al2O3 . SiO2-CaO . Al2O3 . 2 SiO2, CaO . SiO2-CaO . Al2O3 . 2 SiO2 and CaO . SiO2-2 CaO . Al2O3 . SiO2

1993 ◽  
Vol 58 (9) ◽  
pp. 1989-1996 ◽  
Author(s):  
Ladislav Kosa ◽  
Ivan Nerád ◽  
Jozef Strečko ◽  
Ivo Proks ◽  
Katarína Adamkovičová
Keyword(s):  
Binary Systems ◽  
The Other ◽  
Enthalpies Of Solution ◽  
Heat Of Solution ◽  
Differential Heat ◽  
Temperature Range ◽  
Enthalpies Of Mixing ◽  
Other Hand ◽  
Temperature Dependences

Differential enthalpies of solution of components in binary systems 2 CaO . Al2O3 . SiO2-CaO . Al2O3 . 2 SiO2, CaO . SiO2-CaO . Al2O3 . 2 SiO2 and CaO . SiO2-2 CaO . Al2O3 . SiO2 as the function of composition and temperature were determined on the base of isothermal composition dependences of enthalpies of mixing and temperature dependences of heats of fusion of their pure components. From the values of the first differential heat of solution of CaO . Al2O3 . 2 SiO2 and 2 CaO . Al2O3 . SiO2 in CaO . SiO2 over temperature range considered we can conclude that the reactions were closed chains of SiO4 tetrahedra in CaO . SiO2 melt break, are exothermic. On the other hand positive values of this quantity for CaO . SiO2 in CaO . Al2O3 . 2 SiO2 and 2 CaO . Al2O3 . SiO2 led us to the conclusion that the progressive breaking originally closed chains in CaO . SiO2 melt has endothermic character.

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